Jayaraj et al. MWJ 2017, 8:16 Locally transmitted malaria in Tawau, Sabah, Malaysia Vivek J. Jayaraj1*, Dhesi Baharaja2, Navindran Gopalakrishnan1, Yomain Kaco1 1 Centre for Disease Control, Tawau District Health Office 91008, Tawau, Sabah, Malaysia 2 Institute of Medical Research, Ministry of Health, Kuala Lumpur, Malaysia * [email protected] Abstract Background. Tawau was the epicentre of malaria infections in the 1970-1990’s, when industrialisation swept across the state of Sabah, Malaysia. Since then, effective public health intervention, mainly the Malaria Elimination Programme, introduced in 1998, has seen the disease shrivel down into its final elimination phase. Here we retrospectively analyse the case of a 63 year old male with multiple comorbidities who had no exposure to localities with high risk of infection- thus raising the question regarding the means of transmission. Materials and methods. Multiple interviews and an entomological survey were conducted to elucidate the possible mechanism of infection in this patient. Results. Findings point to locally-transmitted malaria, likely introduced by a patient from an endemic region in Tawau. Transmission via this route is rare, and has never before been reported in our setting. Conclusions. This rare case highlights the need for constant vigilance in malaria control and elimination, especially when the target of country-wide elimination is close. 1 Introduction fication based on incidence and risk factors, rigorous health education and disciplined local application on indoor residu- Autochthonous malaria is defined as a malaria infection that al spraying (IRS) and insecticide-treated bednets. This is acquired locally following the import of an infected vec- achievement has resulted in the complete elimination of tor from an endemic area or transmission by local mosqui- malaria in the urban and suburban city centre. All recent toes following the introduction of an infected person [1-4]. cases have been recorded in outlying districts, always near Plasmodium falciparum has a relatively short incubation dense forest reserves or oil palm plantations. Over the last period and is unique in its virulence in that it indiscriminate- 15 years, naturally occurring malaria has not been observed ly infects erythrocytes of all ages [5]. The most important in the urban city centre – the locality at which the case in vector of malaria in Sabah is Anopheles balabascensis, a question resides. mosquito capable flying up to 2 km and breeding in small, temporary water bodies found mostly in dense tropical for- 2.2 Diagnosis and treatment est [6-8]. The patient in question, his wife and son were interviewed 2 Materials and methods during the examination. Clinical diagnosis was made by physicians in Tawau General Hospital, Sabah. Treatment 2.1 Study site and population was also guided by them. All clinical information was re- trieved via case notes made available by the hospital and Tawau is a district on the east coast of Sabah. It is made up also through direct contact with the attending medical offic- of 6125 km2 of diverse geography ranging from urban city ers and physicians. centres with outlying suburban districts, fishing and farming villages, palm oil plantations, logging sites and dense forest. 2.3 Entomological survey The district has a tropical rainforest climate with average temperatures ranging from 26-290C throughout the year. A human landing catch was carried out by trained assistant Generally, November, December and January experience environmental health officers from Tawau Health Office the highest rainfall and February and March are the driest over a period of 3 days in sites at risk of harbouring vectors months. Malaria transmission is observed all year round. within a 2 km radius of both the hospital and the patient’s Since the induction of the Malaria Elimination Programme home. This was carried out in 2 shifts beginning at 6 pm to in 1998, the number of malaria cases has drastically re- 8 am from 20-22 August 2016. A thorough check of the duced. Tawau itself is on the verge of malaria elimination – patient’s housing was also conducted. recording a mere 56 cases in 2016 compared to the thou- sands observed in the 1990’s. This has been achieved through a system of compartmentalising districts and strati- MalariaWorld Journal, www.malariaworld.org. ISSN 2214-4374 1 October 2017, Vol. 8, No. 16 Jayaraj et al. MWJ 2017, 8:16 Table 1. All P. falciparum cases occurring during Sg. Menteri a spike in temperature and was tachypnoeic. He was scored Outbreak 2016. As can be seen there is an overlap during the pa- a GCS 14 initially, but consciousness level floated down to tient’s stay in hospital for cholera and another patient (no. 9) with GCS 8 at one point. He was intubated for airway protection falciparum malaria. and was transferred to the ICU for intensive care and venti- Case no. Age Sex Date of lation. In ICU, he was found to be anaemic. He also suffered notification from an acute kidney injury and metabolic acidosis. He was 1 41 Male 02/06/2016 investigated for causes of acute pyrexia, and found to be 2 40 Female 02/06/2016 positive for Plasmodium falciparum on a blood film stained 3 25 Male 02/06/2016 with Giemsa 6% for identification of malarial parasites. Par- st 4 42 Male 03/06/2016 asite count on the 1 of August was 61511 parasites/µl. He st 5 38 Male 16/06/2016 was started immediately on intravenous artesunate on the 1 6 15 Male 16/06/2016 of August. Response to treatment was immediate. There was 7 23 Female 16/06/2016 improvement in all clinical and laboratory parameters. 8 46 Male 20/06/2016 Blood film on day 2 still exhibited 88700 parasites/µl. On 9 29 Male 11/07/2016 day 3, patient continued to improve, and parasitaemia had 10 34 Male 19/08/2016 dropped to 2900 parasites/µl. All subsequent blood films were negative. He was extubated on day 3 in intensive care, and transferred to a general ward for further care. He was switched from intravenous artesunate to oral artemisinin- 3 Case report lumefantrine combination therapy on day 5 for a further 5 days. He received no transfusion of blood products during The case occurred during the 2nd week of August 2016. A 63 this hospitalisation or the one prior to this. He was dis- -year-old male was suffering from multiple comorbidities at charged 10 days post admission. PCR for malaria confirmed the time of admission. In 2008, he had suffered from a myo- diagnosis as P. falciparum 2 weeks post discharge and all cardial infarction (MI). He underwent a coronary angi- cultures were sterile. ography and was found to have a 2-vessel block. In the The means of infection with malaria in this patient is years following his MI, the patient developed congestive intriguing. Preceding his first admission during this period, cardiac failure. He was classified using the New York Heart dating 1 month prior to 10 July, the patient hardly moved. Association Classification (NYHA) as a Class III. He had He frequented two establishments; for food and drink during also been admitted in 2008 for an upper gastrointestinal this time which was a mere 100 m from his home in the cen- bleed. He was transfused with 2 units of fresh frozen plasma tre of town. He denied travelling anywhere other than these at that point. A subsequent endoscopy uncovered a Forest 3 two places. This was further verified by both his wife and ulcer of his stomach. He was put on proton pump inhibitors son. His heart failure meant travelling anywhere more than a and discharged for follow up under the specialist clinics. He few metres was extremely challenging. The patient also did also suffered from Type 2 Diabetes, chronic kidney disease not own any transportation of his own, fully relying on the Stage 5, open angle glaucoma, benign prostate hyperplasia, rather poor Tawau public transport service. During this peri- and bilateral inguinal hernia. He was under multiple special- od, a locality in Tawau known as Sg. Menteri was undergo- ist clinic follow up for his comorbidities and was on multi- ing a P. falciparum epidemic. It had begun on 2 June 2016, ple medications including Aspirin, Finasteride, Terazocin, and was propagated by hunters incompliant to their prophy- Simvastatin and Glicazide. Due to his multiple problems, he laxis. Cases from this district were reported and even hospi- was judged unfit for surgery and as such simply lived with talised, in close temporal proximity to our patient (Table 1). his many problems. Although he was still able to carry out These patients had been admitted to the ward for antimalari- activities of daily life, he otherwise could not work for ex- al treatment. Two possibilities existed at this point – either tended periods and found travelling extremely difficult. As there were competent anopheline mosquitoes in the immedi- such, he moved into a small room in the centre of town to ate vicinity of the hospital that were capable of transmitting ease the means of travelling about. the parasite from the malaria patients in the ward or these Prior to his admission for malaria, the patient was admit- patient from the Sg. Menteri epidemic who were admitted ted for cholera between the 10-15 July. He had presented during that particular time period had brought in at least one prior to the 10th with a 3-day history of voluminous diar- infectious mosquito which then proceeded to feed on our rhoea and stomach cramps. Upon testing in the emergency patient. department, he tested positive on a stool culture for Vibrio On further history, the nature of this individual’s infec- cholerae.